Method for producing a stator winding of an electric machine, in particular for producing an alternator

ABSTRACT

The invention relates to a method for producing a stator winding ( 18 ) of an electric machine ( 10 ), in particular of an alternator, the stator winding ( 18 ) comprising at least n phase windings ( 120, 121, 122, 123, 124 ) and a phase winding ( 120, 121, 122, 123, 124 ) having several directly consecutively wound coils ( 82 ) having coil sides ( 88 ) and coil side connectors ( 91 ), the coils ( 82 ) being divided into first coils ( 82.1 ) and second coils ( 82.2 ), by means of a forming tool ( 100 ), in which grooves ( 105, 106; 105′, 106 ′) suitable for accommodating the coils ( 82 ) are provided, a first coil ( 82.1 ) being arranged in one groove ( 105; 105 ′) and a second coil ( 82.2 ) being arranged in another groove ( 105; 105 ′), characterized in that n−1 grooves ( 105, 106; 105′, 106 ′) are arranged between the first coil ( 82.1 ) and the second coil ( 82.2 ).

BACKGROUND OF THE INVENTION

DE 103 29 572 A1 discloses a method for producing a core which can beexcited electromagnetically and for whose production a specific statorwinding is used. In comparison to the stator winding disclosed andproduced there, the invention provides for the axial extent of the coilside connectors to be reduced, and therefore for the axial extent of thestator winding to be shortened. In this case, the term “axial” relatesto a rotation axis of a rotor of the electrical machine.

SUMMARY OF THE INVENTION Advantages of the Invention

The method according to the invention for producing a stator winding ofan electrical machine has the advantage that a continuous statorwinding, which consists of one wire, and whose axial extent or axiallength is relatively short can be produced in a relatively simple mannerin this way.

Good matching to the widely different electrical and electromagneticrequirements can be achieved in that each coil has an even or odd numberof turns. This also applies to the situation in which one coil has aneven number of turns and another coil has an odd number of turns.

In one aspect of the invention, coils of a phase winding are shapedafter winding of turns such that the coil sides of one coil are arrangedat least virtually on a plane. This results in the coil side connectorsbeing axially shortened to a particularly major degree, with the axiallength of the winding correspondingly being particularly short. Thestamping of the coil sides of a coil in a stamping tool results in thecapability to fill the slots in the stator core particularly well, andthe slot filling factor (copper cross section of the conductors withrespect to the cross section of the slot) is accordingly particularlyhigh. This improves the cooling of the stator core and of the stator andthe level of space utilization (high electrical output power perphysical volume).

In one aspect of the invention, two directly adjacent coils of a phasewinding have a coil connector between them, which coil connector isconnected integrally to the two directly adjacent coils, wherein onecoil and the other coil are each rotated through an amount ofessentially 90 angular degrees with respect to the coil connector, withthe rotation directions being mutually opposite. This makes it possibleto ensure that the slot cross section can be chosen particularly freely.For example, it is possible for the coil sides at that end of the slotwhich is open radially inward to assume a trapezoidal cross sectionoverall, while the other coil sides, which are arranged between a yokethan the other coil sides just mentioned, are in fact stamped to berectangular.

In one aspect of the invention, one or more phase windings are insertedinto slots of a shaping tool, and in that one group of the coil sides isshifted with respect to another group of the coil sides of the same coiland is shaped such that n−1 slots are arranged between the two groups ofthe coil sides. This has the advantage that, on the one hand, the coilsides close to the yoke can be stamped independently of the coil sideson the slot side. In the final analysis, this means that the stampedcoil sides can be removed from the stamping tool more easily. Incontrast to this, joint stamping of the coil sides which are intended tobe located in one slot has the advantage that this is done at arelatively late time and, in consequence, the handling of the slots oncethey have been stamped is simpler.

In one aspect of the invention, the shaping tool has a lower part, whichis provided with slots, and an upper part, which is provided with slots,with the slots having either the same slot depth or different slotdepths. This allows the individual wire sections to assume a definedposition with respect to one another.

In one aspect of the invention, the coil sides of a coil are stamped ina stamping tool. This chosen arrangement results in a less complex endwinding, thus avoiding excessive flow noise in the electrical machine.

In one aspect of the invention, different coil sides are stampeddifferently. The result is that time is saved in manufacture.

In one aspect of the invention, the coil sides are stamped after windingor after movement. The advantage of the first alternative is that theshaping tool can already be virtually closed, thus allowing the coilsand coil sides to be inserted into the shaping tool without furthersorting problems. The advantage of the second alternative is that theindividual phase windings can be inserted into the tool successively,without the individual phase windings impeding one another in theprocess.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail in the following textusing the figures, by way of example, in which:

FIG. 1 shows a longitudinal section through an electrical machine,

FIG. 2 shows the process of producing a coil,

FIG. 3 shows a section in which the coil is flattened,

FIG. 4 shows a plane view of integrally linked and flattened coils,

FIG. 5 a shows the phase winding, in the initial stage, after the mutualpositioning of the flattened coils,

FIG. 5 b shows a three-dimensional view of the initial stage of thephase winding,

FIG. 6 a shows an initial stage of a phase winding in a shaping tool,

FIG. 6 b shows a three-dimensional illustration, showing how the windingillustrated in FIG. 5 a and FIG. 5 b is inserted in the shaping tool100, and/or the lower part 101 and its upper part 102,

FIG. 7 shows a plan view of the shaping tool 100 and, very particularly,of a lower face 110 of the lower part 101,

FIG. 8 a shows, schematically, the position of all the phase windingsinserted into the shaping tool,

FIG. 8 b shows a three-dimensional view of the phase windings insertedinto the shaping tool,

FIG. 8 c shows an alternative to the insertion method shown in FIG. 8 b,

FIG. 9 shows a side view of the shaping tool after the restriction,

FIG. 10 shows a schematic illustration of a side view of an areainserted into slots in a stator core,

FIG. 11 a and FIG. 11 b show two different slot cross sections,

FIGS. 11 c and 11 d show two different methods for stamping the coilsides which are intended to be located in one slot,

FIGS. 12 a to e show the position of the five phase windings in thestator core, with the individual phase windings having six conductorsper slot,

FIG. 13 shows the position of the phase winding from FIG. 12 a in thestator core which has been bent to be round,

FIGS. 14 a and b show the process of restricting a phase winding for astator having an odd number of coil sides per slot,

FIGS. 15 a to e show the position of five phase windings in the statorcore, with the individual phase windings having five conductors perslot,

FIG. 16 shows the position of the phase winding from FIG. 15 a in thestator core which has been bent to be round,

FIG. 17 shows a further alternative position of the phase windings 120to 124,

FIG. 18 shows various coil connectors on the same end windings,

FIGS. 19 a to c show various embodiments of coil connectors,

FIG. 20 shows a sequence for introducing the winding into the statorcore,

FIGS. 21 a to c show three different types of connection of five-phasewindings,

FIG. 22 shows a schematic slot cross section, and

FIG. 23 shows a schematic longitudinal section through a rotor and astator core.

DETAILED DESCRIPTION

FIG. 1 shows a longitudinal section through an electrical machine 10, inthis case in the form of a generator or alternator for motor vehicles.Inter alia, this electrical machine 10 has a two-part housing 13, whichconsists of a first end frame 13.1 and a second end frame 13.2. The endframe 13.1 and end frame 13.2 hold a so-called stator 16 between them,which on the one hand consists of a substantially annular stator core 17and in whose radially inwardly directed, axially extending slots astator winding 18 is inserted. The radially inwardly directed slottedsurface of this annular stator 16 surrounds a rotor 20, which is in theform of a claw-pole rotor. The rotor 20 consists, inter alia, of twoclaw-pole plates 22 and 23, on whose external circumference claw-polefingers 24 and 25, which extend in the axial direction, are in each casearranged. The two claw-pole plates 22 and 23 are arranged in the rotor20 such that their claw-pole fingers 24 and 25, which extend in theaxial direction, alternate with one another on the circumference of therotor 20. This results in magnetically required intermediate spacesbetween the claw-pole fingers 24 and 25, which are magnetized inopposite senses, and these intermediate spaces are referred to asclaw-pole intermediate spaces. The rotor 20 is borne such that it canrotate in the respective end frames 13.1 and 13.2 by means of a shaft 27and in each case one roller bearing 28, which is located on in each caseone side of the rotor.

The rotor 20 has a total of two axial end surfaces, to each of which afan 30 is attached. This fan 30 consists essentially of a section whichis in the form of a plate or disk, and from which fan blades originatein a known manner. These fans 30 are used to allow air to be exchangedbetween the outside of the electrical machine 10 and the internal areaof the electrical machine 10 via openings 40 in the end frames 13.1 and13.2. For this purpose, the openings 40 are provided essentially at theaxial ends of the end frames 13.1 and 13.2, via which cooling air issucked into the internal area of the electrical machine 10 by means ofthe fans 30. This cooling air is accelerated radially outward by therotation of the fans 30, such that it can pass through the windingoverhang 45, through which cooling air can pass. The winding overhang 45is cooled by this effect. After passing through the winding overhang 45,or flowing around this winding overhang 45, the cooling air follows apath radially outward, through openings which are not illustrated inthis FIG. 1 here.

In FIG. 1, a protective cap 47 is located on the right-hand side andprotects the various components against environmental influences. Thisprotective cap 47 therefore, for example, covers a so-called slipringassembly 49, which is used to supply an exciter current to an exciterwinding 51. A heat sink 53 is arranged around this slipring assembly 49,and in this case acts as a positive heat sink. The end frame 13.2 actsas a so-called negative heat sink. A connecting plate 56 is arrangedbetween the end frame 13.2 and the heat sink 53 and is used to connectnegative diodes 58, which are arranged in the end frame 13.2 andpositive diodes, which are not shown in this illustration here, to oneanother in the heat sink 53, thus representing a bridge circuit, whichis known per se.

Description of the Winding Production

FIG. 2 shows a side view of the process in which a wire 76 is wound ontoan apparatus 70 for winding. The apparatus 70 for winding has twotemplate elements 77, which can be moved with respect to one another inan axial direction. The two template elements 77 have a step 78, thusresulting in a flat area 79 on each template element 77. An oblique coil82 is wound around these flat or low areas 79, bounded by the steps 78in both axial directions. The coil 82 is moved down by pulling thetemplate elements 77 out of the coil 82 from the apparatus 70, see alsoFIG. 3. Alternatively, the wire 76 can also be wound directly ontotemplate elements 77 which are not offset with respect to one another,thus resulting in a coil 82 which is initially not oblique, over twoflat or low areas 79 which are arranged directly opposite one another.The oblique coil 82 is created only when the two template elements 77are offset with respect to one another against the resistance of thecoil 82. In principle, the winding process can in this case be carriedout in two ways: on the one hand, the wire 76 can be wound around thestationary template elements 77 and, on the other hand, the wire 76 canbe wound around the template elements 77 which are rotated about acommon axis. The latter process prevents the wire 76 from being twistedduring the winding process.

FIG. 3 illustrates how the coil 82 is shaped after it has been removedfrom the template elements 77. In the example, the coil 82 has threeturns 85. Each turn 85 has two coil sides 88 which are annotatedseparately by a dot with a further number since this relates to aspecific case of a coil side at a specific position. Therefore, a totalof six coil sides are annotated as the coil sides 88.1, 88.2, 88.3,88.4, 88.5 and 88.6 in the right-hand part of FIG. 3. This successivesequence is based on the sequence in which the coil sides are wound. Thecoil sides 88.1 and 88.2 are integrally connected to one another by acoil side connector 91.1, the coil sides 88.2 and 88.3 are integrallyconnected to one another by a coil side connector 91.2 which is notillustrated, the coil sides 88.3 and 88.4 are integrally connected toone another by a coil side connector 91.3, the coil sides 88.4 and 88.5are integrally connected to one another by a coil side connector 91.4which is not illustrated, and the coil sides 88.5 and 88.6 areintegrally connected to one another by a coil side connector 91.5.

The coil sides 88.1, 88.2, 88.3, 88.4, 88.5 and 88.6 can be seen in FIG.4 a, in the form of a plan view of the flat coil 82 (which is the sameas the coil 82.1) from FIG. 3. The coil sides 88.1 and 88.2 areconnected to one another by the coil side connector 91.1. The two coilsides 88.1 and 88.2 are therefore connected by the coil side connector91.1. The coil sides 88.2 and 88.3 are connected by the coil sideconnector 91.2, the coil sides 88.3 and 88.4 are connected to oneanother by the coil side connector 92.3, the coil sides 88.4 and 88.5are connected to one another by the coil side connector 91.4, and thecoil sides 88.5 and 88.6 are connected to one another by the coil sideconnector 91.5. The coil side connector 91.5 is located above the coilside connectors 91.3 and 91.1, and the coil side connector 91.3 islocated above the coil side connector 91.1. The coil side connector 91.4is located above the coil side connector 91.2.

A first coil connector 94.1 is connected integrally to the coil side88.6 and is in turn followed by a coil side 88.1 and so on—as alreadydescribed for the first coil 82. Initially, the design of the coil 82.2is the same as that of the coil 82.1 already described.

The state as is illustrated in FIG. 4 a was reached by flattening thecoil 82, as illustrated on the left in FIG. 3, see also on the right inFIG. 3. Looking at the illustration in FIG. 3 from left to right, it canthus be seen that the coil side connector 91.2 is located on the coilside connector 91.1 such that the coil side connector 91.1 is crossedover by the coil side connector 91.3, and the coil side connector 91.3is located on the coil side connector 91.2 and crosses over the coilside connector 91.2 and also the coil side connector 91.1, see alsoFIGS. 4 a and 4 b.

In the example shown in FIG. 4 a, each coil 82 is wound with an oddnumber of turns 85. Alternatively, it is also possible without anyproblem to wind an even number of turns 85 onto each coil 82. As will beshown later (FIGS. 14 a and b), it may also be worthwhile to wind aneven number of turns 85 onto coil 82, and to wind an odd number of turns85 onto another coil 82. This is merely a question of the electricalconfiguration of the machine.

According to FIG. 3 and FIG. 4 b, a method is provided according towhich coils 82 of a phase winding are shaped after the winding of turns85 such that the coil sides 88 of one coil 82 are arranged at leastvirtually on a plane. In this case, the turns 85 of a coil 82 arelocated at least partially one on top of the other.

FIG. 5 a illustrates how the previously flattened coils 82 which areintegrally connected to one another are positioned. In comparison to thestate as is illustrated in FIG. 4 b, the coil 82.1 is rotated through90° with respect to the coil connector 94.1. The coil 82.2 is likewiserotated through 90° with respect to the coil connector 94.1. The tworotations of the coils 82.1 and 82.2 are carried out in mutuallyopposite directions, as a result of which the two coils 82.1 and 82.2are rotated through 180° with respect to one another overall. Relativeto the coil side connector 94.2, the coil side connector 94.1 is raisedup. The coil 82.3 is likewise rotated through 90° with respect to thecoil connector 94.2, and this likewise applies in precisely the same wayto the coil 82.2 with respect to the coil connector 94.2. The coils 82.2and 82.3 are rotated in opposite directions, as a result of which theresultant rotations of the two coils 82.2 and 82.3 through 180° withrespect to one another also result in this case. The result of thepositioning and rotation of the individual coils 82.1, 82.2, 82.3, . . .can be seen schematically in FIG. 5 a. For the situation in which, forexample, an arrangement which has 16 poles overall (16-pole embodimentof a phase winding) is provided, a total of 16 coils 82 are positionedwith respect to one another, that is to say the coils 82.1 to 82.16.This positioning and rotation process is carried out for each initialstage and each phase winding which must later be inserted into a statorcore. If the intention is to produce a stator core with three phases,then three phase windings are dealt with in a corresponding manner, andare introduced or inserted into the slots in the stator core. In thecase of five, six or even seven phases, this is carried out analogouslyfor five, six or even seven phases.

A method step is accordingly provided according to which two directlyadjacent coils 82.1, 82.2 of a phase winding have a coil connector 94.1between them, which coil connector 94.1 is connected integrally to thetwo directly adjacent coils 82.1, 82.2, wherein one coil 82.1 and theother coil 82.2 are each rotated through an amount of essentially 90angular degrees with respect to the coil connector 94.1, with therotation directions being mutually opposite.

FIG. 5 b shows a three-dimensional view of the initial stage of thephase winding from FIG. 5 a. This illustration shows the position of theindividual coil sides 88.1 to 88.6. Furthermore, the coil sideconnectors 91.1 to 91.5 are illustrated, as well as a start 95 of thecoil 82.1. The following coils 88.2 to 88.4 are likewise illustratedanalogously to FIG. 5 a.

FIG. 6 a shows a side view of a shaping tool 100. The shaping tool 100is formed essentially from two parts and has a lower part 101 and anupper part 102.

Both the lower part 101 and the upper part 102 have a substantiallycuboid external contour. Slots are in each case introduced on one sideof the lower part 101 and on one side of the upper part 102. These slotsin the upper part 102 and the slots in the lower part 101 are oppositeone another, in such a way that two mutually opposite slots form acommon area. The slots are introduced both in the upper part and also inthe lower part such that they extend in a straight line between two endfaces. The number of slots in the upper part 102 preferably correspondsto the number of slots in the lower part 101, and preferably to thenumber of slots in the stator 16. In this case, the lower part 101 hasan end face 108, and the upper part has an end face 109. The slots 105are introduced in the lower part 101, and the slots 106 are introducedin the upper part. Compared with the initial stage of the phase windingillustrated in FIG. 5 a, this is inserted into the slots 105 in thelower part 101, in the manner in which its coils 82.1 etc. arepositioned. The individual coils 82.1, 82.2, 82.3 etc are in this casespaced apart such that, in the case of a stator winding with five phasewindings, four slots are arranged between the coils which are directlyintegrally adjacent alongside one another. If this is a stator windingwhich has three phase windings, then two slots are arranged between theindividual coils 82, analogously to this. If this is a five-phase statorwinding, then, in the same way as in the figure, four slots 105 and 106are arranged between the individual coils 82.

In consequence, a method is described for producing a stator winding inan electrical machine 10, in particular an alternator, with the statorwinding 18 having at least n phase windings and a phase winding having aplurality of directly successive wound coils 82 with coil sides 88 andcoil side connectors 91, with the coils 82 being subdivided into firstand second coils. Furthermore, a shaping tool 100 is provided, in whichthere are slots 105 and 106 which are suitable for holding the coils 82.A first coil is a coil at a specific position in the initial stage ofthe phase winding or the phase winding itself, while a second coil isanother coil 82, which follows the first coil as the next coil 82.Provision is accordingly made for a first coil to be arranged in oneslot and for a second coil to be arranged in another slot. Correctly,n−1 slots are arranged between the first coil and the second coil 82.

FIG. 6 b illustrates, three-dimensionally, how the winding illustratedin FIG. 5 b and FIG. 5 a is inserted in the shaping tool 100, or thelower part 101 and its upper part 102.

In the side view shown in FIG. 7, the coil side connectors 91.2 and 91.4can be seen, see also FIG. 4 a. Furthermore, the coil connectors 94.1and 94.2 are illustrated, likewise in a schematic view. At the lower endof the shaping tool 100, the coil side connectors 91.1, 91.3 and 91.5project out of the slots 105 and 106. In the illustration in FIG. 7,only one initial stage of a phase winding is illustrated, as is alsoalready the case in FIG. 6.

FIG. 8 a shows a schematic illustration, in which a total of five phasewindings and their initial stages are inserted in the shaping tool 100,to be precise the two tool parts the lower part 101 and the upper part102. The coil connectors illustrated here are all arranged behind thelower parts 101 and upper parts 102, as seen by the viewer in FIG. 8 a.This likewise applies to the coil connectors 94.2 for the individualphase windings.

FIG. 8 b shows a three-dimensional view of the arrangement shown in FIG.8 a. The five initial stages of the phase windings are inserted in theshaping tool 100. This arrangement in the shaping tool 100 comprises atotal of five phase windings, which are intended for a stator core whichhas eighty radially inwardly open slots. According to the configurationshown here, six conductors, which are stacked one on top of the other,are provided in each slot in the stator core which will finally beproduced later. The five phase windings 120, 121, 122, 123 and 124 havein this case been plugged into the parts of the shaping tool 100 whichhave previously been fitted to one another, the lower part 101 and theupper part 102, from their axial end surface 130 and 131, into the slots105 and 106, respectively.

FIG. 8 c illustrates an alternative to the insertion method shown inFIG. 8 b. According to FIG. 8 c, an upper part 102 is provided, in whoseslots 106 the individual phase windings, or their initial stages, areinserted for this purpose. While, in the case of the exemplaryembodiment shown in FIG. 8 b, no sequence need be defined for whichphase winding is inserted into the slots 105 and 106 first of all, andall that need be considered is how the individual coil connectors 91.2should be arranged with respect to one another, according to theexemplary embodiment shown in FIG. 8 c, a precise sequence must becomplied with respect to the position of the individual coil connectors94.2 and the further coil connectors 94.3, 94.4 etc. In order to make itpossible to achieve the structure as illustrated in FIG. 8 b of theposition of the individual coil connectors 94 in the shaping tool 100,it is necessary according to the embodiment variant shown in FIG. 8 cfor the individual phase windings to be inserted into the upper part 102of the shaping tool in a specific sequence. Thus, it is necessary firstof all to start with the phase winding 124, before then inserting thephase winding 123, which is followed by the phase winding 122 and thenin turn by the phase winding 121 in order then, finally, to insert thephase winding 120. This sequence results in the arrangement of the coilconnectors 94.2 as shown in FIG. 8 b. Once the five phase windings 120to 124 in the example have been inserted into the upper part 102, thelower part 101 is placed on the winding or the upper part 102. This stepis not illustrated here, but, after this step, the situation is the sameas that illustrated in FIG. 8 b.

The intention is for all the phase windings 120 to 124 to be held at thesame time in the shaping tool 100 in order to be shaped at the sametime. In this case, provision is made for the axial length of the coilconnectors 94 not to be reduced, while the axial length or extent of thecoil side connectors 91 is reduced during the shaping process.

Alternatively, the phase windings 120 to 124 may also be inserted intothe lower part 101. The sequence of the phase windings to be insertedmust then be adapted, if the aim is to achieve the same result as inFIG. 8 b. Accordingly, the phase winding 120 is then inserted first,followed by the phase winding 121, then the phase winding 122, then thephase winding 123, and then the phase winding 124.

As has already been described with reference to FIG. 8 b or FIG. 8 c,the intention is to insert the phase windings 120 to 124 into theshaping tool 100 either in the direction of the coil sides (FIG. 8 b) ortransversely with respect thereto. Insertion of the coil sides 88transversely with respect to the shaping tool 100 means that themovement direction during insertion into the shaping tool has at leastone component which is directed at right angles to the coil sides 88 andthe wire direction.

FIG. 9 illustrates the next step, which follows the arrangement shown inFIG. 8 b. For the sake of clarity, only the phase winding 120 isillustrated here. The other phase windings 121 to 124, which are notillustrated here, are subject to precisely the same process, with thecorresponding phase windings only being inserted in each case offset byone slot 105 in the lower part 101 and one slot 106 in the upper part102. As explained above, each coil 82 has coil sides 88. These coilsides 88.1, 88.3 and 88.5 form a group 130. This group 130 has thefeature, according to which this is inserted in the lower part 101, andinto a slot 105 there, without projecting into the slot 106 in the upperpart 102.

Furthermore, another group 133 can be seen, which comprises the coilsides 88.2, 88.4 and 88.6. The coil sides 88.2, 88.4 and 88.6 in thisgroup 133 have the common feature that these coil sides 88 are insertedin a slot 106 in the upper part 102, and do not extend to such an extentthat they project into a slot 105.

These features of the groups 130 and 133 have the purpose of in this waydefining a separating plane 136, in which no coil sides 88 are locatedand, in consequence, this separating plane 136 cannot be blocked by thecoil sides 88, in particular by the coil sides 88.5 and 88.2. This isimportant because the upper part 102 should be moved with respect to thelower part 101. According to the further method step which is nowprovided, there is provision that the upper part 102 is moved relativeto the lower part 101 corresponding to the arrow 139 in order in thisway to move the coil sides of the group 133 with respect to the coilsides 88 of the group 130 to such an extent that the coil sides 88 inthe group 133 come to rest with respect to a further group 130 in a slot105 associated with another coil, specifically the coil 82.2. In thiscase, the group 133 is moved to such an extent that n−1 slots 105 arearranged in the movement direction of the coil sides 88 after themovement between the two groups 130 and 133 of a coil 82. Since n isfive in this exemplary embodiment, there is a separation of four slots105 between the group 130 of the coil 88.1 and the group 133 of the coil82.1. A method is accordingly provided according to which one or morephase windings 121, 122, 123, 124, 125 are inserted into slots 105, 106;105′, 106′ in a shaping tool 100, and each coil 82 has coil sides 88,with a group 133 of the coil sides 88 being moved with respect toanother group 130 of the coil sides 88 of the same coil 82, and beingshaped, such that n−1 grooves are arranged at 105 between the two groups130, 133 in the movement direction of the coil sides 88. If theexemplary embodiment were to comprise a three-phase design, then thenumber of slots 105 between the two groups 130 and 133 would be twoslots 105. In the case of a six-phase design, the separation would ben−1=5, and in the case of a seven-phase design, the separation would ben−1=6 slots 105.

It is intended that all the phase windings 120 to 124 will be held atthe same time in the shaping tool 100, in order to be shaped at the sametime. However, in principle, it is also possible to shape the phasewindings 120 to 124 individually, each on their own, in order to fit thephase windings 120 to 124 to one another only after this has been done.

The windings are removed from the tool by removing the upper part 102from the lower part 101 in the subsequent radial direction (stackingdirection of the coil sides 88), and by only then removing the windingfrom the tool. The upper part 102 and the lower part 101 must thereforebe movable with respect to one another on two planes or in two axialdirections (later circumferential direction and later radial direction).

FIG. 10 shows, highly schematically, a view of coil sides 88. Incontrast to the exemplary embodiment described above, this slot section140 does not have six coil sides 88.1 to 88.6, but five coil sides 88.1to 88.5. This is because, during production for example as shown in FIG.8 a or 9, first and second coils 82 have different numbers of turns. Forexample, a first coil has three turns, while a second coil has twoturns. A constellation such as this results in five coil sides aftermovement as shown in FIG. 9, which are arranged one on top of the otherand can thus be inserted into one slot in a stator core. On theleft-hand side of FIG. 10, r denotes the direction which indicates theincrease in the radius starting from a subsequent center point of around stator core. In other words: the lower coil side connector 91.1 islocated radially furthest outward, while the coil side connector 91.5 isarranged radially furthest inward. The coil side connectors 91.1 and91.3 which are located radially furthest outward in FIG. 10 areoriginally coil side connectors of a second coil with only two turns,while the coil side connectors 91.1 to 91.5 which are located radiallyfurther inward are the coil side connectors of a first coil with threeturns. This phenomenon will also be described at another point later inthe description.

FIG. 10 shows a final state of a slot section 140 and of junction areas149 which are in each case arranged on both sides of the slot section140. Outside the junction areas 149, there are in each case adjacent endwinding areas 152. According to the envisaged method step, there is around wire cross section, as sketched at a, before stamping, over theentire length of the section 146, of the junction area 149 and also ofthe end winding area 152 for the individual wire sections, which are notreferred to here in any more detail. The intention with shaping orstamping is to carry out shaping from the cross-sectional area sketchedwith a or under a or the section 146 such that the wires no longer havea round cross section, but such that the external contour of thetotality of all the coil sides 88 has a trapezoidal external contour(envelope), c). This trapezoidal contour is intended to be stamped inthe same mold over the entire section 146 which will be inserted in aslot in a stator core, see also b) and d). A junction area 149 which hasa length of a few millimeters in each case starts at the final positionsof the section 146. At the end of the junction area 149 which is remotefrom the section 146, the junction area 149 merges into the alreadymentioned cross section, as has been described with reference to a). Thecross-sectional area—as is sketched here for e), is the same as that ofa). According to the invention, the junction area is stamped in adefined manner and represents a contour which merges continuously fromthe trapezoidal cross section to the round cross section of theindividual wires in the axial direction (rotation axis of the rotor)with respect to the electrical machine.

It is accordingly envisaged that the coils 82 are provided with astamped junction area 149 between coil sides 88 and coil side connectors91.

FIG. 11 a and FIG. 11 b show, in the form of a detail, side views of thecross section of two slot sections 140 of two different exemplaryembodiments. This slot section 140 is inserted in a slot 158 between twoteeth 155. While the left-hand slot in FIG. 11 a has core sides 88.1 to88.5 with a trapezoidal cross section overall, the slot 158 in FIG. 11 bhas a somewhat more complex slot cross section. For example, the slotcross section in the area of the slot section 159 is rectangular, whileit is once again trapezoidal in the slot section 160. In this case, theposition of the coil sides 88.1 to 88.5 is as follows: the coil side88.1 is radially furthest outward with respect to the stator core 17,while the coil side 88.5 is radially furthest inward. As can be seensimply by comparison with FIG. 10, cross section b) with the crosssection from FIG. 10 a), stamping of the slot section 140 results in thewires or wire cross sections, which originally had a round crosssection, being shaped such that, for example, the radially inner coilside 88.5 is crushed to a relatively major extent in the circumferentialdirection.

As shown in FIG. 11 a) and FIG. 11 b), the intention is for the coilsides 88.1 to 88.5, and therefore different coil sides, to be stampeddifferently. As is shown in FIG. 11 c and FIG. 11 d, the intention isfor the coil sides 88 to be stamped in a stamping tool 186. While,according to the schematic FIG. 11 c, this is possible, for example, inan early stage of the winding process, for example shortly after windingthe coil 82, with the coil sides 88.1, 88.3 and 88.5 first of all beinginserted into a stamped slot 189, which is separated from a stamped slot190 for the coil sides 88.2, 88.4 and 88.6. The coil 82 is then alsostamped by means of a stamping diode 193 before the movement of the coilsides, as shown in FIG. 9. Alternatively, according to FIG. 11 d, it isalso possible to stamp the coil sides 88.1 to 88.5 in a stamped slot 196jointly and once by means of a stamping diode 193 in a subsequent methodstep, for example after constriction.

The stamping according to FIG. 11 d) can also be carried out such thatall the phase windings 120 to 124 with all their coil sides are shapedat the same time in one stamping tool 186 (for example afterconstriction).

In order to make the illustration clearer, FIGS. 12 a) to e) illustratethe stator core 17 after insertion of the phase windings 120 to 124, asa result of which the individual phase windings 120 to 124 are eachillustrated separately in the stator core 17. The individual phasewindings 120 to 124 are in principle of the same design. The differencebetween the individual phase windings 120 to 124 is only because theyare each inserted into the stator core 17 offset by one slot from thestart. The phase winding 120 which is inserted into slot 1 at the starthas a so-called winding overhang 163. Since this stator core is a statorcore 17 which is produced using the so-called flat-pack technique, forexample see also the initially cited document, a stator core 17 such asthis is formed by stacking of individual essentially straight laminates166. These laminates 166 are in general coincident at least in the slotarea and are stacked in the direction of the slots 158, thus resultingin a substantially cuboid laminate pack or stator core 17. Theselaminates 166 are normally connected to one another during the course ofthis pack production process, for example by means of weld beads on arear face 169 of a yoke 172 or in the inside of the slot, to form asolid pack. After all the phase windings 120 to 124 have been insertedinto the stator core 17, this is bent round such that the openings orslot apertures 175 of the slots 158 face radially inward. The two endsurfaces 177 and 176 are in this case placed on one another and are thenconnected to one another in an interlocking manner by means of aconnection technique such as welding. The stator core is then completewith the stator winding 18, and can be installed in the electricalmachine 10, to be precise between the two end frames 13.1 and 13.2.

The phase winding 120 is in this case positioned in the stator core 17as follows: in this case, as described above, the single phase windingis on the basis of FIG. 2 up to and including FIG. 9. In the state shownin FIG. 9, the phase winding has its phase connection 95 at right anglesto the plane of the sheet, and the phase connection 95 is directedbehind the lower part 101. The phase winding 120 illustrated in FIG. 9has been rotated with respect to FIG. 12 a, effectively about the arrow136 in FIG. 9, such that, after rotation and as shown in FIG. 12 a, thephase connection 95 is arranged at the top on the left, that is to sayin slot 1 in the outermost slot position. A coil side 88.1 extends fromthis phase connection 95 in the first slot position in the slotdirection behind the stator core 17, in order to merge there after thejunction into the coil side connector 91.1 and, after entering the slotposition 4 in slot 6, into the coil side 88.2. From there, the wireemerges from the slot 6 and merges there into the coil side connector91.2, which enters the slot position 2, that is to say the penultimateoutermost radial position in the slot 1, on the front face of the statorcore 17. There, the wire merges into the coil side 88.3. From there, thewire then passes into the coil side connector 91.3, and then into thecoil side 88.4 (slot position 5, penultimate innermost position), inorder once again to merge from there into the coil side connector 91.4,which merges into the third position and the coil side 88.5. The wireleaves the slot 158 on the rear side of the slot 1 in the slot position3, once again merges into a coil side connector, specifically the coilside connector 91.5, which again emerges there after passing through theslot 6 at the radially innermost position and the existence as a coilside 88.6, and merges into the radially outermost position at theradially innermost position as the coil connector 94.1. The individualfurther stations of the wire are in this case outlined briefly asfollows:

Entry into slot 11, radially innermost position (slot position 6), coilside 88.1, then

Coil side connector 91.1,

Slot 6, slot position 3, coil side 88.2;

Coil side connector 91.2;

Coil side 88.3 (penultimate innermost radial slot position), slotposition 5,

Coil side connector 91.3,

Entry into the penultimate outermost slot position in slot 6, coil side88.4,

Coil side connector 91.4,

Coil side 88.5, slot 11, slot position 4,

Coil side 91.5,

Coil side 88.6, slot 6, radially outermost slot position,

Slot position 1, junction into the coil connector 94.2 which merges overthe radially outermost position, that is to say from slot 6, slotposition 1, into slot 11, slot position 1.

The phase winding 120 then physically ends in the already mentionedwinding overhang 163, which is theoretically located at a slot position81, but can later be inserted into the slot 1 shortly before completionof the process of bending the stator core 17 round. This windingoverhang 163 consists of three coil sides 88.1, 88.3 and 88.5. However,the phase winding end does not end in the overhang, but still in thestator core, see also FIG. 12.

As already mentioned, the phase winding 121, FIG. 12 b, is offset by oneslot in a corresponding manner, and starts at slot 2, at the sameposition with respect to the slot position. This also applies to thephase winding 121, which starts in the slot 3, to the phase winding 123which starts in the slot 4, and to the phase winding 124, which startsin the slot 5. The winding overhang 136 of the phase winding 121 istherefore theoretically located at the slot position 2, and issubsequently inserted into the slot 2, before completion of the processof bending round, onto the coil sides 88.1, 88.3 and 88.5 which arealready located there. The phase winding 121 likewise has a windingoverhang 163, which, however, is located at the slot position 3 and isaccordingly inserted later into the slot 3 onto the coil sides 88.1,88.3 and 88.5, before completion of the process of bending round. Thewinding overhang 163 of the phase winding 123 is located at the slotposition 4, and is inserted into the slot 4 onto the coil sides 88.1,88.3 and 88.5 before the process of bending round, to be precise beforethe completion of the process of bending round. In the same way, thewinding overhang 163 of the phase winding 124 is located at the slotposition 5 before completion of the process of bending round into theslot 5 onto the coil sides 88.1, 88.3 and 88.5.

According to the exemplary embodiment shown in FIG. 12, starting fromthe respective end 176 or 177, there are in each case n phaseconnections 95 in the first n slots 158, and n phase connections 180 inthe last n slots 158.

The coils 82 are in each case, so to speak, formed by two layers. Thatis to say the coil sides 88 are arranged in (2) radially differentlayers.

Furthermore, the coil sides (88.1, 88.3, 88.5; 88.2, 88.4, 88.6) of eachtypical second coil 82.2 (82.4, 82.6, 82.8, 82.10, 82.12, 82.14, 82.16)are located in two slots 158, in which case two coil connectors 94.1 and94.2 are connected to form two coil sides 88.1 and 88.6 of adjacentcoils 82.1 and 82.3, that is to say they in each case connect the firstand the last coil side of an adjacent coil, in which case these coilsides 88.6 and 88.1 are inserted in the same slots 158 as the coil sides88.1, 88.3, 88.5; 88.2, 88.4, 88.6 of the coil 82.2 located betweenthem.

FIG. 13 shows the phase winding 120 in the stator core 17 after thestator core 17 has been bent round, with the respective phase windings120 and 124. For the sake of simplicity and clarity, the phases 121 to124 have not been illustrated here. As has already been indicated inFIGS. 12 a to e, the position of the other phase windings 121 to 124 issimply offset by one slot with respect to the respectively precedingphase windings, starting with the phase winding 120. Furthermore, aphase connection 180 and a weld bead 183 can be seen, which weld bead183 connects the two ends 177 and 176 to one another. The stator core 17has a substantially central opening 184. FIG. 13 shows theconnection-side view of the stator 16, which is normally that side whichfaces the rectifier in the electrical machine 10 which is in the form ofan alternator.

Furthermore, the stator 16 can also be described by stating that in eachcase at least one group of single-layer coil connectors 94.1; 94.2 of aplurality of phase windings 120, 121, 122, 123, 124 is arranged on theinternal circumference and on the external circumference of the statorcore 17, with the coil connectors 94.1; 94.2 being arranged inimmediately adjacent slots 158, and crossing one another. Coil sideconnectors 91 of a plurality of phase windings 120, 121, 122, 123, 124are arranged between one group of single-layer coil connectors 94.2 onthe external circumference of the stator core 17 and one group ofsingle-layer coil connectors 94.1 on the internal circumference of thestator core 17.

FIGS. 14 a and b show one exemplary embodiment of the production of aphase winding 120 which has five coil sides 88 in each slot. As hasalready been explained with reference with FIG. 3, a first coil 82.1with three turns 85 and a second coil 82.2 with two turns 85 are woundfor this purpose. This sequence is repeated the correspondingly requirednumber of times, thus resulting, overall, in a winding with sixteencoils 82, by way of example.

Analogously to the processes which have been explained in conjunctionwith FIGS. 4 a, 4 b and 5 a, the individual successive coils 82 are eachrotated through 90°, thus resulting in the configuration illustrated inFIG. 14 for the individual phase winding.

In order that the position of the individual coils 82.2 and 82.4—anentirely general form of the coils which have fewer turns 85 than othercoils 82—is such that the lower part 101 can be moved relative to theupper part 102, the slots in the upper part and lower part, which areintended to hold coils 82.2 and 82.4 with few turns 85, are equippedwith a shallower slot depth than the other slots. When the number ofphases is 5, this means that a further five slots 105′ and 106′ followfive slots 105 and 106 which hold coils 82.1, 82.3, . . . with moreturns 85, with the five slots 105′ and 106′ holding the coils 82.2,82.4, . . . with fewer turns 85. When the number of phases is 3, 6 or 7,3, 6 or 7 of these slots 105, 105′, 106, 106′ in each case follow oneanother. Following the insertion of all the phase windings 120 to 124(not illustrated), the upper part 102 is moved relative to the lowerpart 101. Since the phase windings 120 to 124 are not all arranged inone layer after the constriction process, with said layer comprisingonly the five intended slot positions in the stator core 17, the phasewindings 120 to 124 which are arranged in a total of six slot positionsin the shaping tool 100 have to be moved in their own right in order toreach the five intended slot positions.

Accordingly, with reference to FIGS. 6 a and 14, there is provision thatthe shaping tool 100 has a lower part 101, which is provided with slots105, 105′, and an upper part 102, which is provided with slots 106,106′, with the slots 105, 106 either having the same slot depth (FIG. 6a) or different slot depths (FIG. 14).

A second exemplary embodiment of five phase windings is illustrated in avery similar manner in FIGS. 15 a to 15 e. In contrast to theillustration shown in FIGS. 12 a to e, these five phase windings 120 to124 have only five coil sides 88 in each slot 158. This thereforeinvolves the coils having different numbers of turns. The first coil,like the phase windings shown in FIG. 12 as well, admittedly has threeturns. However, in comparison to the first coil, the second coil now hasonly two turns. A coil 82.1 is correspondingly disclosed which has anodd number of turns, and a coil 82.2 is disclosed which has an evennumber of turns. In this case, in the exemplary embodiment shown in FIG.14, the coil 82.1 is a first coil, and the other coil 82.2 is a secondcoil. The production method for the phase windings 120 to 124, as isshown in FIG. 15, is correspondingly slightly different from that shownin FIG. 6 a: while, as before, the coil 82.1 has three turns, the coil82.2 now has only two turns. A shaping tool, as is illustrated inprinciple in FIG. 6 a, is therefore somewhat different for production ofthe phase windings 120 to 124 as shown in FIG. 15 because the slots 105and 106, respectively, in the lower part 101 and in the upper part 102would be somewhat shallower starting from the separating plane 136 atthe position of the second coil 82.2, see also FIGS. 14 a and b. Forexample, coming from the first coil 82.1, the coil connector 94.1 iscorrespondingly inclined somewhat with respect to the separating plane136, in order then to project into the slot 106′, directed somewhatcloser to the separating plane 136. The coil connector 94.2correspondingly projects out of the slot 105′ at a position which isarranged somewhat closer to the separating plane 136. In the slot 105where the coil 82.3 is located, the coil connector 94.2 then once againprojects into the slot 105 once again at the position which is furthestaway from the separating plane 136.

While the arrangement illustrated in FIG. 13 has a stator core 17 and astator 16 which has five phases which are arranged in 80 slots with sixconductors in each slot, that is to say six coil sides 88 in each slot,FIG. 16 likewise illustrates a five-phase stator 16 in an entirelyanalogous manner, whose phase windings 120 to 124 are arranged in 80slots with five coil sides 88 in each slot 158.

FIG. 16 shows that view of the stator 16 which is normally associatedwith a rectifier. The side opposite the rectifier is normally that side,the one input drive side, that is to say facing an end frame, which isclosest to a pulley disk, in any case an input drive for the rotor.

With reference to FIG. 17, the following text describes how the phasewindings 120 to 124 can be inserted into the stator core 17alternatively to one another. While, in FIG. 17 a, the phase winding 120is inserted in precisely the same way as is the case in FIG. 12 a, incomparison to FIG. 12 b, those coil sides of the phase winding 121 whichpreviously formed the winding overhang 163 are inserted into the secondslot, with the phase connection 95 and the connection 180 being arrangedon the same side of the stator core 17 as are the connections 95 and180, respectively, of the phase winding 120. In other words: althoughthe phase winding 121 is produced in precisely the same way as the phasewinding 120, it is, however, rotated, to be precise through 180°, aboutan axis 190 which is oriented in the stacking direction of the laminates166.

Once again, the phase winding 122 is inserted into the stator core 17 inprecisely the same way as is the case in FIG. 12 c as well; the phasewinding 123 is once again rotated about the axis 190 with respect to thephase winding 120, and is at the same time once again inserted into thestator core 17, starting in the fourth slot, as in FIG. 12 d. As can beseen from FIG. 17 b, the phase winding 121 likewise starts in the secondslot, in the same way as the phase winding 121 shown in FIG. 12 b. Thephase winding 124 is arranged in precisely the same way as in FIG. 12 e.Once again, the phase windings 121 to 124 have winding overhangs 163which occupy the same slots and extend to the same slot positions as inthe case of the exemplary embodiment shown in FIG. 12. However, thewinding overhangs of the phase windings 121 and 123 are of differentdesign, and each have a phase connection 95.

According to the exemplary embodiment shown in FIG. 17, starting fromthe respective end 176 or 177, there are in each case n phaseconnections 95 in the slots 158 in the area of the end 176. The phaseconnections 180 are distributed in the slots 158 in the area of the end177 and in the area of the end 176.

FIGS. 18 a to d show two different exemplary embodiments of end windings152 on that side of the stator 16 which is closest to the rectifier. Forexample, an end winding 152 can be provided radially on the outside suchthat a coil connector 94.2 in a group of coil connectors 94.2 whichconnect the first coils 82.1 to second coils 82.2 is not triangular, inthe same way as the others, but is quadrilateral. By way of example, onthe inside of this end winding 152, the intermediate spaces between thelimbs on one side of triangular coil connectors 94.1 are closed with anencapsulation 300 or with an adhesive layer 303. However, it is alsopossible to close all the intermediate spaces in a group of coilconnectors 94.3. Both can be embodied as alternatives.

FIGS. 18 c and 18 d show various arrangements of coil connectors 94. Forexample, in the exemplary embodiment illustrated there, only rectangularcoil connectors 94.1 and 94.3 are formed on the inside of the endwinding 152, and are furthermore staggered or stepped (increasingmaximum deflection of the end winding). In contrast, the coil connectors94.2 and 94.4 radially on the outside are uniform and triangular.

FIG. 19 shows a view of a stator core 17 as shown in FIGS. 12 a to 12 b,according to which the phase windings 120 to 124 have been inserted intothe stator core 17. The corresponding detail shows the slots 158 at theposition 6 up to and including the slot 158 at the position 25. In thiscase, the coil connectors 94.1 and 94.2 are configured such that theyextend axially outward in a triangular shape. Each coil connector 94.1crosses other coil connectors 94.1 a total of four times. This alsoapplies to the coil connectors 94.2 in FIG. 17 a. The coil connectors94.1 may but need not be triangular, as shown in FIG. 19 a, but may justas well be curved (semicircular). In any case, these curved coilconnectors would likewise cross adjacent coil connectors 94 a total offour times.

The exemplary embodiment shown in FIG. 19 b illustrates the situationfor a stator core 17 having the phase windings 121 to 124 as shown inFIG. 17. The coil connectors 94.1 are distributed uniformly over thecircumference of the stator core 17 and, also in the flat state, overthe entire length of the stator core 17. By way of example, this has theadvantage that there are no discontinuities on the circumference of thestator, as a result of which the noise that is developed is fairlyuniform. FIG. 19 c shows a modification of the exemplary embodimentshown in FIG. 19 b, according to which the coil connectors 94.1 projectin a rectangular shape on one side out of the slots 158, and assumedifferent positions in the axial direction on the other side. This hasthe advantage that the so-called end winding or end winding areas 152does or do not extend so much in the radial direction. The end windingor the end winding area 152 has a smaller radial extent than theexemplary embodiments shown in FIGS. 19 a and 19 b.

FIGS. 20 a to d show the various assembly sequences. For example,provision is initially made for the insulation films 200 to be insertedinto the slots 158 after the provision of the stator core 17. In onepreferred embodiment, insulation films are designed such that their endswhich are directed in the direction of a tooth head 203 still end in theslot 158 underneath the tooth head 203, without narrowing the slotopening 175, see also FIG. 20 b. After the insertion of the insulationfilm, the phase windings 120 to 124 are inserted into the alreadyinsulated stator core 17. The cross sections of the core sides 88 of thephase windings 120 to 124 have previously been shaped and, in theprocess, the cross section has been matched to the slot shape, with thestator core 17 in the bent round state. The aim of shaping of the wirewhich is round in the initial state is not to radially enlarge the endwinding 152. In consequence, it is provided that those coil sides whichare intended for a slot 158 have a height h2 over their entire radialextent, which height h2 is greater after the shaping or stamping of thecoil sides 88 of a slot than the height h1 of the totality of the coilsides 88 which are intended for one slot 158. The height h1 is in thiscase the sum of the unstamped coil sides 88.1 to 88.5 (copper crosssection with a lacquer or resin insulation). After the insertion, FIG.20 c, of the coil sides 88 of the phase windings 120 to 124, the statorcore 17 is bent round, thus creating a cylindrical orannular-cylindrical stator core and, overall, a stator 16.

As shown in FIGS. 21 a, b and c, different types of connection to oneanother are provided for the phase windings 120 to 124 for a five-phasestator winding 18, and a rectifier circuit is provided. As shown in FIG.21 a, a so-called magic-symbol circuit (five-phase pentagram circuit orcircuit in the form of a five-pointed star) is provided, and accordingto FIG. 21 b a five-phase star circuit is provided, with a five-phasepentagon circuit or five-phase ring circuit being provided according toFIG. 21 c.

The stator winding 18 of the electrical machine 10 is intended to beequipped with n phase windings 120, 121, 122, 123, 124, in which case atleast one phase winding 120, 121, 122, 123, 124 is intended to beproduced according to one of the already described exemplaryembodiments.

A stator 16 is provided for an electrical machine 10, with this stator16 having a stator core 17 and the stator core 17 having a substantiallycentral opening 184, having slots 158 and teeth 170 in the stator core17, which are open radially inward toward the central opening 184,having a stator winding 18 with a specific number n, greater than unity,of phase windings 120, 121, 122, 123, 124, with sections of a phasewinding 120, 121, 122, 123, 124 being arranged in a plurality of slots158 and, in this case, with coils 82 with coil sides 88 being arrangedin a plurality of slots 158, with a plurality of coil sides 88 of a coil82 having a plurality of turns 85 being inserted, stacked one on top ofthe other, into a slot, and with a plurality of other coil sides 88 ofthe coil 82 being inserted into another slot 158 and being stacked,wherein a stator winding 18 is located in the slots of the stator 16, asdescribed.

Alternatively, the stator can also be described as follows: a stator 16is provided for an electrical machine 10, with this stator 16 having astator core 17 and the stator core 17 having a substantially centralopening 184, having slots 158 and teeth 170 in the stator core 17, whichare open radially inward toward the central opening 184, having a statorwinding 18 with a specific number n, greater than unity, of phasewindings 120, 121, 122, 123, 124, with sections of a phase winding 120,121, 122, 123, 124 being arranged in a plurality of slots 158 and, inthis case, with coils 82 with coil sides 88 being arranged in aplurality of slots 158, with a plurality of coil sides 88 of a coil 82having a plurality of turns 85 being inserted, stacked one on top of theother, into a slot, and with a plurality of other coil sides 88 of thecoil 82 being inserted into another slot 158 and being stacked, with thephase winding 120, 121, 122, 123, 124 having a plurality of such coils88.1, 88.2 which are integrally connected to one another directlysuccessively, with two coils 82.1, 82.2 which are integrally connectedto one another directly successively being connected to one another onan internal circumference of the stator core 17 by a single-layer coilconnector 94.1, and with two coils 82.2, 82.3 which are integrallyconnected to one another directly successively being connected to oneanother on an external circumference of the stator core 17 by asingle-layer coil connector 94.2.

Preferably, the number of conductors z per slot in the phase windings120 to 124 should be 6, and the wire diameter should in this case bed=1.95 mm, with the insulation being designed for level 2. In this case,the wire originally has a round cross section and is stamped to a slotshape or slot shape section which corresponds to its slot position. Thefilling factor, that is to say the ratio of the wire cross sectionslocated in a slot including the wire insulation (lacquer, resin) to theslot cross section (iron) should be less than 75%.

As shown in FIG. 22, a slot cross section has the following dimensions:

d1 a=140 mm, d1 i=106 mm, the axial length le (in the rotation axisdirection of the rotor) should be 37 mm. The total number of slots 158should be 80. In one special embodiment, the angle z for 79 slots shouldbe approximately 4.51°. The diameters d1 and d2 should be 131.3 mm and108 mm, respectively. The distances c1 and c2 between centers of thesymmetrical slot 158 are 2.2 and 1.6 mm, respectively. The radii r1 andr2, which are each 0.3 mm, originate from these distances betweencenters, that is to say from the respective end points of the twoindicated lengths. The slot opening has a width of 1.45 mm. The slotopening is rounded with a radius r3=0.3 mm on the side facing the slot158; toward the internal diameter, the slot opening is rounded with aradius r4=0.3 mm. The maximum width of a tooth at the tooth head is 2.04mm. The slot pitch Tau1 at the slot base is 5.16 mm, while the slotpitch Tau2 at the tooth head is 4.24 mm. In the vicinity of the slotbase, the tooth width is bz1=2.36 mm. The tooth width in the vicinity ofthe slot base is measured at right angles to the radial direction fromthe center of the tooth at the point at which the tooth merges with aradius r2 into the curvature of the tooth head. The yoke height hJ is4.05 mm. For the copper area (conductor without any insulation), thistherefore results in an area of 17.9 mm² for a slot area of 30.5 mm².This therefore results in a copper filling factor of 58.8.

FIG. 23 shows a schematic longitudinal section through the stator core17 and the rotor 20. The external diameter dp is intended to be 105.3mm, and the diameter of the shaft 27 is intended to be 17 mm. The numberof poles, that is to say the number of claws, is intended to be 16. Theother indicated variables are the pole core diameter dk, the pole corelength lk, the plate thickness lpk of a claw pole, a chamfer which isdefined on the one hand by the angle betakl and the length ls, theinternal diameter di2 at the claw tip, the diameter dpka in theintermediate space between two claw poles, and a diameter at thetheoretical intersection between the underneath of the claw pole and theinner end surface 210 of a plate.

1. A method for producing a stator winding (18) of an electrical machine(10), wherein the stator winding (18) has at least n phase windings(120, 121, 122, 123, 124) and a phase winding (120, 121, 122, 123, 124)has a plurality of directly successive wound coils (82) with coil sides(88) and coil side connectors (91), with the coils (82) being subdividedinto first coils (82.1) and second coils (82.2), the method comprisingusing a shaping tool (100), in which slots (105, 106; 105′, 106′) areprovided which are suitable for holding the coils (82), with a firstcoil (82.1) being arranged in one slot (105; 105′) and a second coil(82.2) being arranged in another slot (105; 105′), and arranging n−1slots (105, 106; 105′, 106′) between the first coil (82.1) and thesecond coil (82.2).
 2. The method as claimed in claim 1, characterizedin that each coil (82) is wound with an even or odd number of turns(85).
 3. The method as claimed in claim 1, characterized in that onecoil (82) is wound with an even number of turns (85), and another coil(82) is wound with an odd number of turns (85).
 4. The method as claimedin claim 3, characterized in that one coil (82) is a first coil (82.1)and the other coil (82) is a second coil (82.2), with n−1 slots (158)being arranged between the first coil (82.1) and the second coil (82.2).5. The method as claimed in claim 1, characterized in that coils (82) ofa phase winding (120, 121, 122, 123, 124) are shaped after winding ofturns (85) such that the coil sides (88) of one coil (82) are arrangedat least virtually on a plane.
 6. The method as claimed in claim 5,characterized in that the turns (85) of a coil (82) are located at leastpartially one on top of the other.
 7. The method as claimed in claim 5,characterized in that two directly adjacent coils (82.1, 82.2) of aphase winding (121, 122, 123, 124, 125) have a coil connector (94.1)between them, which coil connector (94.1) is connected integrally to thetwo directly adjacent coils (82.1, 82.2), wherein one coil (82.1) andthe other coil (82.2) are each rotated through an amount of essentially90 angular degrees with respect to the coil connector (94.1), with therotation directions being mutually opposite.
 8. The method as claimed inclaim 7, characterized in that one or more phase windings (121, 122,123, 124, 125) are inserted into slots (105, 106; 105′, 106′) of ashaping tool (100), and in that one group (133) of the coil sides (88)is shifted with respect to another group (130) of the coil sides (88) ofthe same coil (82) and is shaped such that n−1 slots (105, 106; 105′,106′) are arranged between the two groups (130, 133) of the coil sides(88).
 9. The method as claimed in claim 8, characterized in that theshaping tool (100) has a lower part (101), which is provided with slots(105, 105′), and an upper part (102), which is provided with slots (106,106′), with the slots (105, 106) having either the same slot depth ordifferent slot depths.
 10. The method as claimed in claim 1,characterized in that the coil sides (88) of a coil (82) are stamped ina stamping tool (186).
 11. The method as claimed in claim 10,characterized in that different coil sides (88) are stamped differently.12. The method as claimed in claim 10, characterized in that the coilsides (88) are stamped after winding or after movement.
 13. The methodas claimed in claim 10, characterized in that the coils (82) areprovided with a stamped junction area (149) between coil sides (88) andcoil side connectors (91).
 14. A stator winding (18) having n phasewindings (120, 121, 122, 123, 124), characterized in that at least onephase winding (120, 121, 122, 123, 124) is produced according to themethod of claim
 1. 15. A stator (16) for an electrical machine (10),with this stator (16) having a stator core (17) and the stator core (17)having a substantially central opening (184), having slots (158) andteeth (170) in the stator core (17), which are open radially inwardtoward the central opening (184), having a stator winding (18) as setforth in claim 14 with a specific number (n), greater than unity, ofphase windings (120, 121, 122, 123, 124), with sections of a phasewinding (120, 121, 122, 123, 124) being arranged in a plurality of slots(158) and, in this case, with coils (82) with coil sides (88) beingarranged in a plurality of slots (158), with a plurality of coil sides(88) of a coil (82) having a plurality of turns (85) being inserted,stacked one on top of the other, into a slot, and with a plurality ofother coil sides (88) of the coil (82) being inserted into another slot(158) and being stacked.
 16. A stator (16) for an electrical machine(10), with this stator (16) having a stator core (17) and the statorcore (17) having a substantially central opening (184), having slots(158) and teeth (170) in the stator core (17), which are open radiallyinward toward the central opening (184), having a stator winding (18)with a specific number (n), greater than unity, of phase windings (120,121, 122, 123, 124), with sections of a phase winding (120, 121, 122,123, 124) being arranged in a plurality of slots (158) and, in thiscase, with coils (82) with coil sides (88) being arranged in a pluralityof slots (158), with a plurality of coil sides (88) of a coil (82)having a plurality of turns (85) being inserted, stacked one on top ofthe other, into a slot, and with a plurality of other coil sides (88) ofthe coil (82) being inserted into another slot (158) and being stacked,characterized in that the phase winding (120, 121, 122, 123, 124) has aplurality of such coils (88.1, 88.2) which are integrally connected toone another directly successively, with two coils (82.1, 82.2) which areintegrally connected to one another directly successively beingconnected to one another on an internal circumference of the stator core(17) by a single-layer coil connector (94.1), and with two coils (82.2,82.3) which are integrally connected to one another directlysuccessively being connected to one another on an external circumferenceof the stator core (17) by a single-layer coil connector (94.2).
 17. Thestator (16) as claimed in claim 16, characterized in that in each caseat least one group of single-layer coil connectors (94.1; 94.2) of aplurality of phase windings (120, 121, 122, 123, 124) is arranged on theinternal circumference and on the external circumference of the statorcore (17), with the coil connectors (94.1; 94.2) being arranged inimmediately adjacent slots (158), and crossing one another.
 18. Thestator (16) as claimed in claim 17, characterized in that coil sideconnectors (91) of a plurality of phase windings (120, 121, 122, 123,124) are arranged between one group of single-layer coil connectors(94.2) on the external circumference of the stator core (17) and onegroup of single-layer coil connectors (94.1) on the internalcircumference of the stator core (17).
 19. The stator (16) as claimed inclaim 16, characterized in that one or more coil connectors (94.1) is orare arranged in a triangular, rectangular or semicircular shape.
 20. Thestator (16) as claimed in claim 16, characterized in that intermediatespaces between coil connectors (94) are closed with an encapsulation(300) or with an adhesive layer (303).
 21. An electrical machine (10)having a stator (16) as set forth in claim 15.